RU2144557C1 - Method of processing motor alkylate into mixtures with vacuum gas oil - Google Patents

Abstract

FIELD: petrochemical processes. SUBSTANCE: vacuum gas oil is subjected to catalytic cracking in mixture with motor alkylate containing no higher than 300 ppm sulfur: high-boiling by-product produced on plants for alkylation of isobutane with olefins in presence of sulfuric acid, which contains no high-octane hydrocarbon. Motor alkylate is fed into bottom part of reactor barrel in amounts 1 to 5% of the weight of vacuum gas oil. EFFECT: increased yield of gasoline components and octane number of gasoline and subsequent reduction of sulfur level.

Description

 The invention relates to methods for processing vacuum gas oil and motor alkylate and can be used in the oil refining industry. Known methods for carrying out catalytic cracking of vacuum gas oil in a fluidized bed reactor of a microspherical zeolite-containing catalyst (CCF) (Cracking of oil fractions on zeolite-containing catalysts. / Ed. By S. N. Khadzhiev. M: Chemistry, 1982, p. 280. Glozman A. B. et al. Oil refining and petrochemistry, 1982, N 10, p. 10-12). The reactor is an inclined pipe on which a cylindrical glass is mounted. The latter has an upper bottom and windows for changing the direction of the vapor flow and the catalyst, as well as reducing the dust content of the gas stream at the outlet of the cyclones.

 A disadvantage of the known methods is the high sulfur content in cracked gasoline in the absence of hydrotreatment of raw materials, which creates problems when compounding modern reformulated grades of high-octane gasolines.

 A known method of producing alkylbenzene by alkylation of isoparaffins with olefins in the presence of sulfuric acid, according to which the alkylate is subjected to rectification to obtain alkylbenzene and motoalkylate (SU 1101440 A1, 07.07.84).

 The disadvantage of this method is that the motor alkylate cannot be used for compounding in the preparation of commercial gasoline due to the high temperature of the end of boiling (in terms of fractional composition it corresponds to diesel fractions).

 The closest solution in technical essence and the achieved results is a method for processing vacuum gas oil by catalytic cracking in the presence of a zeolite-containing catalyst, according to which, to increase the yield of cracked gasoline, 0.00001 - 0.1 wt.% Organic additives with surface - are added to the vacuum gas oil active properties (RU 2054026 C1, 02/10/96).

 The disadvantage of the method adopted for the prototype is the reduced yield of cracked gasoline (not more than 33.9 wt.% For raw materials).

 The aim of the invention is to increase the production of high-octane components of gasoline while reducing the sulfur content in cracked gasoline and increasing its octane number (OCh).

 The goal is achieved by a method of processing vacuum gas oil by catalytic cracking in the presence of a microspherical zeolite-containing catalyst, according to which a mixture of vacuum gas oil and motorcycle alkylate containing not more than 300 ppm sulfur of a high boiling point by-product obtained from isobutane alkylation plants with olefins in the presence of sulfuric acid in which there are no high octane hydrocarbons is processed. and which is fed to the bottom of the glass of the reactor of the catalytic cracking unit in an amount of 1-5 wt.% from vacuum gas oil.

 The method of processing motorcycle alkylate mixed with vacuum gas oil according to the proposed technical solution allows to increase the production of high-octane components of gasoline and reduce their sulfur content by conversion under the conditions and on the catalyst of the CCF process of motorcycle alkylate.

 An essential distinguishing feature of the proposed method in comparison with the method adopted for the prototype is that the catalytic cracking of vacuum gas oil is carried out in the presence of an additive - motor alkylate, which is a high boiling point by-product obtained from isobutane alkylation units with olefins in the presence of sulfuric acid and in which high octane hydrocarbons are absent. The sulfur content in motorcycle alkylate usually does not exceed 300 ppm.

 Thus, the claimed method meets the criteria of the invention of "novelty."

The method is as follows. The non-purified vacuum gas oil is subjected to catalytic cracking in the presence of a microspherical zeolite-containing catalyst. The raw material enters the dispersant for mixing with water vapor and then through the nozzle it is fed to the capturing device of the transport line, where it comes into contact with the regenerated catalyst, mixed with it and enters the reactor glass. In the zone of the fluidized bed, limited by the volume of the reactor vessel, catalytic cracking of the feed proceeds. A motor alkylate (sulfur content - 290 ppm, fractional composition: NK 184-198 ^o C, KK 310-321 ^o C) in the amount of 5 wt.% From vacuum gas oil taken for processing is fed to the bottom of the reactor glass.

 Motoalkylate is a by-product resulting from the production of the high-octane component of gasoline by alkylation of isobutane with olefins in the presence of sulfuric acid. After contacting, the reaction mixture, consisting of acid, isobutane and reaction products, after settling of the spent acid, acid and alkaline purification, is subjected to rectification to obtain recycle isobutane, alkylbenzene and heavy reaction products - motor alkylate, in which there are no high-octane hydrocarbons.

 Analysis of known technical solutions for the processing of vacuum gas oil and motor alkylate allows us to conclude that there are no signs similar to the essential distinguishing features of the claimed method, that is, the compliance of the proposed method with the requirements of an inventive step.

 The advantages of the proposed method are illustrated by the following examples.

 Example 1

 The high octane component of gasoline (alkylbenzene) is obtained by alkylating isobutane with olefins in the presence of sulfuric acid. After contacting, the reaction mixture, consisting of acid, isobutane and reaction products after sludge waste acid, acid and alkaline purification, is subjected to distillation to obtain recycle isobutane, alkylbenzene and heavy reaction products - motoalkylate.

Non-purified vacuum gas oil of West Siberian oil (up to 360 ^o C boils 4 wt.%, 95% - 491 ^o C, coking 0.11 wt.%) Is subjected to catalytic cracking in the presence of industrial microspherical zeolite-containing catalyst DA-250 having a bulk density of 981 kg / m ³ , conversion (MAT) 67.8%, coke 0.18%, particle size distribution, wt.%: over 200 microns - 4; 160-200 microns - 5; 100-160 microns - 25; 60-100 microns - 46; less than 60 microns - 20.

Raw materials heated in heat exchangers and furnaces to a temperature of 400 ^o C, enters a remote disperser, where the raw materials are pre-mixed with water vapor and then fed through a nozzle to the capturing device of the transport line. In the latter, the raw material comes into contact with the regenerated catalyst coming in from the regenerator at a temperature of 550-670 ^o C, mixes with it and enters into the reactor glass through the distribution line through the distribution grid. In the zone of the fluidized bed, limited by the volume of the reactor vessel, catalytic cracking of the feed proceeds.

 A motor alkylate (sulfur content - 290 ppm) is fed to the bottom of the beaker in the amount of 5 wt.% Of the vacuum gas oil taken for processing.

 Process parameters and flow characteristics are given in the table.

 Example 2

 The catalytic cracking of a vacuum gas oil is carried out according to Example 1.

 A motor alkylate (sulfur content - 110 ppm) is fed to the bottom of the beaker in an amount of 1 wt.% Of the vacuum gas oil taken for processing.

 Process parameters and flow characteristics are given in the table.

 Example 3

 The catalytic cracking of a vacuum gas oil is carried out according to Example 1.

 A motor alkylate (sulfur content - 230 ppm) is fed to the bottom of the reactor glass in an amount of 3 wt.% Of the vacuum gas oil taken for processing.

 Process parameters and flow characteristics are given in the table.

 Example 4

 The non-purified vacuum gas oil of West Siberian oil according to Example 1 is subjected to catalytic cracking in the presence of an equilibrium industrial microspherical zeolite-containing catalyst DA-250 without feeding the motor alkylate to the bottom of the reactor glass.

 The parameters and characteristics of the fractions are given in the table.

 Thus, the process according to the proposed method (examples 1-3) allows to increase the production of gasoline components by 0.5 - 2.0 wt.%, While the cracked-gasoline OCh will increase by 0.3-0.5 points, and the content sulfur in it decreases by 3-10% rel. in comparison with cracked gasoline obtained without feeding a glass of a motor alkylate reactor to the bottom.

Claims (1)

 A method of processing vacuum gas oil by catalytic cracking in the presence of a microspherical zeolite-containing catalyst, characterized in that they process a mixture of vacuum gas oil and motorcycle alkylate - containing not more than 300 ppm of sulfur of a high boiling point by-product obtained from isobutane alkylation plants with olefins in the presence of sulfuric acid, in which there are no high octane hydrocarbons which is fed to the bottom of the glass of the reactor of the catalytic cracking unit in an amount of 1 to 5 wt.% of vacuum gas oil.

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